A preparative route is proposed for the synthesis of the novel heterocyclic systems 7-oxo-and 1,2,7-trioxo-1,2-dihydropyrano[3,2-e]indole using classical Fischer and Sandmeyer methods respectively. We have studied various conditions for cyclization of the starting coumarin 6-isonitrosoacetamide and the methyl or ethyl pyruvate 6-coumarinylhydrazones. The syn-and antiform ratio of the latter and the structure of all of the synthesized compounds were determined using spectroscopic data analysis.Keywords: 6-(isonitrosoacetamido)coumarin, 7-oxo-1,2-dihydropyrano[3,2-e]indole, Sandmeyer reaction, Fischer reaction, syn-Z-and anti-E-forms of pyruvate ester 6-coumarinylhydrazones, 1,2,7-trioxo-1,2-dihydropyrano[3,2-e]indole, cyclization.In continuing our study of condensed compounds containing a pyrrole ring [1-4] it was of interest to synthesize tricyclic systems which included indole and coumarin fragments. The interest in such a system is a result of the variety of the nature of the physiological activity of indole derivatives [5][6][7][8][9][10][11][12] and also the possibility of their use in the synthesis of alkaloids and alkaloid related substances.We have used classical Sandmeyer and Fischer reactions for the "addition" of a pyrrole ring to the bicyclic coumarin system (see Scheme).In the first case, the starting 6-aminocoumarin (1) was converted to the "isatin" 3 via the isonitrosoacetamide 2. In the second, the hydrazine hydrochloride 4 was obtained from the same amine via a diazonium salt and was then reacted with methyl or ethyl pyruvate to give the corresponding hydrazones 5a,b. Cyclization of the latter gave the target compounds 6a,b. _______ * Dedicated to the memory of a dear teacher, the prominent Russian science professor Nikolai Nikolaevich Suvorov. Founder of indole chemistry in Georgia. In love with, and a warm favourite of, Georgia. __________________________________________________________________________________________

2005Benzopyran derivatives R 0350 7-Oxo-3,7-dihydro-and 1,2,7-Trioxo-1,2,3,7-tetrahydropyrano[3,2-e]indoles. -A coumarin-based synthesis of tricyclic condensed systems with an indole moiety in the molecule like in (III) and (V) is reported for the first time. -(KHOSHTARIYA, T. E.; BOCHOIDZE, L. T.; BATSIKADZE, K. T.; Chem. Heterocycl.

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2005 Benzopyran derivatives R 0350 Pyrrolocoumarins. Part 1. Synthesis and Spectroscopic Investigation of 7-Oxoand 1,2,7-Trioxo-1,2-dihydropyrano[3,2-e]indole and Their Derivatives. -A series of title compounds of type (IV), (VII), (IX), and (XI) is prepared. -(KHOSHTARIYA*, T. E.; KURKOVSKAYA, L. N.; BOCHOIDZE, L. T.; BATSIKADZE, K. T.; MIRZIASHVILLI, N. T.; ABESADZE, I. G.; SIKHARULIDZE, M. I.; TURABELIDZE, V. G.; ANANIASHVILI, V. O.; DZHASHI, T. O.; et al.; Chem. Heterocycl.